Re: toning "lumen" prints

Chris,
The chemistry is a little different here from exposure and chemical
development of B&W papers. For the chemical development only latent exposure
needs to be formed. Very few silver atoms get reduced, not enough to form a
visible image.
For the lumen print (or any POP process) you start with a silver chloride
emulsion and reduce some of the silver through the photochemical means.
Actually you need to reduce a lot of silver. That silver is trapped in the
silver chloride matrix and this what gives the colour. These are the pinks
and plumes, etc of the POP processes (salted paper, albumen, etc). If you
tone it with gold at that stage you can replace some of the colloidal silver
with gold and preserve the color. If you do not tone and put it in the fixer
it will dissolve the remaining silver halide and the colloidal silver
trapped in it. I suppose if you expose it long enough you can reduce enough
silver to just fix it without toning.
Because colloidal gold has such a rich color varaition it adds so much to
lumen prints.
Marek

>From: "Christina Z. Anderson" <zphoto@montana.net>
>Reply-To: alt-photo-process-l@usask.ca
>To: alt-photo-process-l@usask.ca
>Subject: Re: toning "lumen" prints
>Date: Sat, 17 Jun 2006 13:10:41 -0600
>
>Good, Marek,
>I thought you might pull through for me :)
>I will throw that little bit of info out now.
>I wonder if scientifically it is true that elemental silver does not tone,
>but that the Lumen prints are not totally reduced to elemental silver and
>maybe the unreduced active silver halide still tones. I mean, you have
>proven that experientially lumen prints tone, so it is a moot point. But I
>am surprised that this source is wrong on the theoretical point. Maybe
>Ryuji has an answer for this?
>Chris
>----- Original Message ----- From: "Marek Matusz" <marekmatusz@hotmail.com>
>To: <alt-photo-process-l@usask.ca>
>Sent: Saturday, June 17, 2006 10:50 AM
>Subject: RE: toning "lumen" prints
>
>
>>Chris,
>>Good to hear from you again. Lumen prints tone very well. You tone after
>>exposure, before fixing. Toning is very much dependent on the paper that
>>you use. Warm tone forte paper tone beautifully in gold or platinum toner
>>preserving a lot of delicate color hues that arise during long exposures.
>>See some examples
>>http://www.alternativephotography.com/artists/marek_matusz.html
>>Marek, Houston
>>
>>
>>>From: "Christina Z. Anderson" <zphoto@montana.net>
>>>Reply-To: alt-photo-process-l@usask.ca
>>>To: "Alt, List" <alt-photo-process-L@usask.ca>
>>>Subject: toning "lumen" prints
>>>Date: Fri, 16 Jun 2006 22:11:56 -0600
>>>
>>>Good evening all,
>>>Can't seem to shake "China time"--up late at night, sleep til noon in the
>>>morning...hmmmm.
>>>
>>>I slugged through 140pp of notes from time immemorial, and came across a
>>>statement by a very reputable black and white source who said that when a
>>>print exposed in the sun as per Burchfield's lumen prints (intense, long
>>>sun exposure, no development, just fixing, as per our discussion back in
>>>sept. or oct.) the silver halide is reduced to elemental silver, which
>>>does not tone.
>>>
>>>However, I have also in my notes from either Liam Lawless, Kees or
>>>someone on this list from years ago (2000?) that toning works great with
>>>POP paper (not traditional POP but POP you create from normal enlarging
>>>paper). I am way too lazy to take my print into the school's darkroom at
>>>the moment and see if it tones--anyone doing lumen prints lately can help
>>>me out here? I tend to believe Liam/Kees' statement...
>>>Chris
>>>
>>>
>>
>>
>>
>
>
Received on 06/17/06-02:28:22 PM Z